Locomotive boiler firebox



OCL 27,1942- B. E. LARsoN l LocQMoTIvE B'OILER'FIREBOX Filed Nov. 27, 1940 Patented ct. 2.7, 1942 STATES LOCOMOTIVE BOILER FIREBOX Bert E. Larson, Park Ridge, Ill., assigner to Locomotive Firebox Company, Chicago, Ill., a corporation of Delaware 2 Claims.

This invention relates to improvements in locomotive boiler iireboxes and it consists of the matters hereinafter described and more particularly pointed out in the appended claims.

One of the objects of the present invention is to provide a locomotive boiler firebox having relative large heating surface so as to increase the water steaming and circulating eciency of the rebox without increasing vits size.

A further object of the invention is to provide a locomotive boiler flrebox including a water tube supported fire arch and one or more water steaming and circulating elements disposed entirely within the space above the arch and whereby the arch not only functions for its intended purpose but also protects parts of said elements against direct contact by flames in the firebox.

Also, it is an object of the invention to provide a locomotive boiler firebox which is safe in use even under low water conditions by keeping the crown sheet thereof ooded at all times.

The above mentioned objects of the invention, as well as others, together with the advantages thereof will more fully appear as the specification proceeds to describe the preferred embodiment of the invention..

In the drawing:

Fig. l is a longitudinal vertical sectional View through the rebox end of a locomotive boiler embodying the preferred form of the invention.

Fig. 2 is a transverse vertical sectional view through the rebox end of the boiler as taken on the line 2 2 of Fig. 1.

Referring now in detail to that embodiment of the invention illustrated in the accompanying drawing, the locomotive boiler firebox therein shown comprises a re chamber which extends from the back sheet 5 to the flue sheet 6 and `from one to the other of the side sheets 1, the

back plate I4 are formed to provide a fuel door opening I5.

The sheets and plates mentioned define the side water legs I6 and the front and rear water legs I'l and I8 respectively of the boiler, which I9. The inner sheets defining the iirebox and the outer or wrapper sheets are staybolted together in the usual manner.

2li-20 indicate conventional arch supporting members in the form of laterally spaced tubes, each fixed at their front ends in the upper portion of the front throat sheet 9. Said tubes extend upwardly and rearwardly from said throat sheet and are xed at their rear ends in the back sheet 5, at an elevation above the fuel door opening I5. The fire arch, which is indicated as a whole at 2|, is constituted by side, center and intermediate rows or courses of brick Z2- 23 and 24'respectively as appears in Fig. 2. The brick of the center and intermediate rows are supported solely by the arch tubes 2li while the brick of the side rows are supported at their inner sides upon the two outermost arch tubes and are supported at their outer sides upon the side sheets of the lirebox in the usual manner.

The arch, of course, takes its longitudinal inclination from the arch tubes Zll and the rear end of said arch is disposed at an elevation above that of the door opening I5 and is spaced some distance forwardly of the back sheet 5.

The above may be taken as descriptive of a conventional locomotive boiler firebox having a fire arch therein supported by arch tubes. Under re conditions, the products of combustion are deflected or directed rearwardly to pass over the rear end of the arch on their way to the flues I0 in the flue sheet.

According to the present invention I am enabled to increase the water steaming and circulating elciency, as well as the safety factor of the boiler by providing a plurality of thermic syphons 25 and 26 of such shape and form that they may be disposed in the space between the arch 2| and the crown sheet 8. Said syphons are arranged in a laterally spaced relation and do not obstruct the flame passageway of the firebox above the rear end of the arch.

Each syphon includes a flat hollow body 2l having opposed side walls 28-23, front and rear end walls 29 and 30 and a bulged bottom 3l. The side walls 28-28 are parallel while the front and rear end walls are disposed at converging angles. All of said walls terminate at the top in a lateral flange 32 that is welded in an elongated opening in the crown sheet. The open top of said body forms the water discharge for the ysyphon into the boiler water space above the crown sheet.

The rear end of the bulged bottom 3l merges are closed at their bottom ends by the mud ring into a rounded corner 33 forming a part of the rear wall of the syphon, while the front end of the bulged bottom is connected to a single inlet neck 34 only. The bulged bottom and the inlet neck are disposed at a more shallow angle of inclinaticn than the arch 20 so that more vertical clearance is provided between the arch and the iront end of the syphon body than between the rear end of the arch and the closest point on the syphon body.

l The inlet neck 34 of each element is connected by a curved portion 35 to a laterally and outwardly inclined tubular inlet portion 36 having its extremity welded in a collar provided therefor in the associated side sheet of the rebox toward its front end. Said inlet portion takes in water for the associated side water leg, and the passage of said water through said neck 34 and its portions 35 and 36 is always in an upward direction into the syphon body.

Itis to be noted that the body of the syphon has a considerable length relatively to its vertical depth and that the rear end of the body has a considerable overhang with respect to the rear end of the arch. With this arrangement of parts, while the space available for the syphons is relatively small, the syphon bodies provide relatively large evaporating surface areas. Thus, the provisions of the syphons described adds materially to the active area of the rebox and increases the steaming and circulating e'ciency of the boiler as a whole.

The body and inlet neck of the syphon are disposed high enough above associated parts of the arch to readily permit replacement of such arch brick as may require replacement., Also, the greater part of the bulged bottom 3| of each syphon is protected by the arch from direct name contact with the re in the firebox, so that fire checking of the bulge portion of the syphon is materially reduced, if not entirely eliminated.

The present invention also makes it possible readily to convert arch tube reboxes already in service, into syphon equipped reboxes and this with relatively small expense. Again, the construction described increases the safety factor of i the boiler by keeping the crown sheet of the nrebox flooded with water at all times.

Cil

While in describing the invention I have referred in detail to the form, arrangement and construction of the parts involved, the same is to be considered as illustrative only, so that I do not wish to be limited thereto, except as may be specically set forth in the appended claims.

I claim as my invention:

1. In combination with a locomotive type boiler rebox including a crown sheet, side sheets and front and back sheets and an arch tube supported fire arch extending upwardly and rearwardly from a point adjacent the front sheet to a point spaced forwardly of the back sheet, and water circulating and steaming means arranged in the rebox entirely above the arch, said means including a plurality of laterally spaced elements, each having a flat hollow body disposed entirely above the arch and longitudinally of the rebox and having an elongated discharge opening through the crown sheet, the bottom of said body extending upwardly and rearwardly of the re- -box and having an intake tube opening through the adjacent side sheet at a point above the front end of the arch, the hollow body of each element having a portion disposed rearwardly of the rear end of the arch.

2. In combination with a locomotive type boiler rebox including a crown sheet, side sheets, a front sheet and a back sheet, arch tubes extending upwardly and rearwardly from a lower portion of the front sheet to an upper portion of the back sheet, means providing a re arch above the arch tubes and supported at least in part thereon, and which arch terminates at its rear end at a point spaced forwardly of said back sheet and a water steaming and circulating element arranged in the rebox above the arch with the arch interposed between the element and the re in the rebox, said element including a flat hollow body having opposed side walls, converging front and rear walls and an inclined bottom, said body having a single elongated discharge opening at its top that opens through the crown sheet and an inlet opening at its lower end that communicates with a single opening in the boiler above the fire arch. v

BERT E. LARSON. 

